The goal of this work is to describe the patterns of body size variation in Late Holocene human populations of Pampa and Continental Patagonia in order to discuss the evolutionary processes which may have shaped them. The null hypothesis indicates that random evolutionary processes would explain this variation, while the alternative hypothesis refers to non-random processes, like directional selection or phenotypic plasticity, linked to temperature. Spatial comparative methods (simple correlation and variation partition analysis) were combined with those derived from quantitative genetics (divergence rate analysis). Also, the agreement between observed variation and biological expectations from experimental studies was evaluated. Femur dimensions were used as proxies of size through traditional morphometrics. The results suggest an adjustment to a north-south gradient that couples a climatic gradient: higher latitudes are associated with lower temperatures and larger body sizes, rejecting the null hypothesis. Differences in size are mainly explained in terms of the interaction between environment and space; therefore, there is a common effect between both. The relevance of ecologic factors on body size divergence was corroborated after the results of divergence rate the analysis. The pattern fi ts a model of body size increase with the consequent reduction in the loss of heat due to a decrease in the surface area/volume ratio. In this way, divergence in body size with respect to climate could be explained as the result of directional selection associated with cold temperatures, so that the average size of individuals increased with lower temperatures.